This proposal supports the acquisition of two mass spectrometers for use by 16 biomedical investigators of whom 10 are funded by the NIH and two are starting faculty members. A Matrix -assisted laser desorption ionization (MALDI) time-of-flight mass spectrometer and an electrospray ionization LC/MS/MS instrument will be added to an established core mass spectrometry service facility in the School of Chemistry and Biochemistry at the Georgia Institute of Technology and Georgia State University, along with numerous smaller schools in the region. This center complements a successful, established high resolution shared NMR center located at Georgia State University. The purchase of the mass spectrometers will be supported by matching funds of $149,680 from Georgia Tech and $16,000 from Georgia State University. The mass spectrometers will be used for the rapid, molecular mass determination of high molecular weight proteins and nucleic acids, and will be used for a broad spectrum of biochemical analyses. The users represent a highly productive group of investigators with interests in drug design, structural biochemistry, and molecular biology. The user group is strengthened by several faculty members at Georgia Tech who are performing cutting edge research in several fields of mass spectrometry. The mass spectrometers will be used in the design of new synthetic inhibitors for protease of therapeutic importance, for determining whether DNA is a conductor or an insulator, for investigating the role of selenium in human metabolism, determining the nature of the changes that occur in lens protein in cataracts, and in the design of anti-HIV and anticancer drugs.